Item response theory analyses of the Delis-Kaplan Executive Function System card sorting subtest

Area of Science:

• Cognitive Psychology
• Neuropsychology
• Developmental Psychology

Background:

• Executive functions are crucial for cognitive development.
• The Delis-Kaplan Executive Functioning System (D-KEFS) is a widely used assessment tool.
• Understanding the psychometric properties of subtests like Card Sorting is essential for accurate interpretation.

Purpose of the Study:

• To examine the dimensionality of the 16-item Card Sorting subtest.
• To test for measurement invariance across age and gender using item response theory (IRT).
• To identify potential differential item functioning (DIF) in the Card Sorting subtest.

Main Methods:

• Exploratory factor analysis (EFA) was used to determine the factor structure.
• Item response theory (IRT) models were applied to test for measurement invariance and DIF.
• Multigroup analysis was conducted on a sample of 264 children aged 9-15.

Main Results:

• A two-factor model distinguishing verbal and perceptual items best fit the data.
• Measurement invariance was supported across age groups but violated across gender groups.
• Two items showed differential item functioning (DIF) for males and females; females scored higher on perceptual ability, and scores increased with age for both genders.

Conclusions:

• The Card Sorting subtest has a two-factor structure (verbal and perceptual).
• While generally invariant across age, gender-specific DIF necessitates caution in interpreting results for males and females.
• Findings highlight the need to consider gender and age when interpreting Card Sorting performance in children.